Fungicidal compositions



United States Patent lier Carbon and Chemical Corporation, a corporation of California No" Drawing. Application February 10, 1956 SerialN'o. 564,639

9 Claims. (Cl. 167-22) This invention relates to fungicidal compositions, and

in particular concerns compositions of such character in which an organo-phosphorus' polymer is employed as the essential active ingredient.

H In copending application, Serial No. 518,390, filed June 27, 1955, there is described a class of polymeric materials obtained by reaction between an alkylene oxide or sulfide with a lower alkyl trithiometa'phos phate. These materials vary in physical form from viscous liquids torubber-like or resinous solids, and are disclosed to be useful as lubricant additives, extenders and plasticizing agents for synethetic resins, etc.- The present invention is based on our discovery that these polymeric materials are highly toxic to a variety of fungus organisms, and may be formulated with conventional toxicantadjuvants to form a variety of fungicidal compositions useful as" sprays, impregnants, dusts, and the like. By reason of their polymeric nature these products have very low volatilities (and hence do not readily evaporate when used in the open air) and. are stable to hydrolysis.

As stated, the active ingredient of the present compositions is formed by reaction between a lower" alltyl trithioinetaphosphate, i. e., a compound of the formula RSPS' wherein R represents an alkyl group containing from 1 to 4 carbon atoms, and an alkylene oxide or sulfide. The latter reactants may be defined by the formula wherein R represents hydrogen, and or a1ky1,.n represents a whole number less than 2, and X represents oxygen or sulfur. Examples of such compounds include ethylene oxide, proplyene oxide, trimethylene oxide, styrene oxide, ethylene sulfide, n-butyl-ethylene sulfide, propylene sulfide, p-methylstyre'ne sulfide, etc. The trithiometaphosphate reactant is exemplified by methyl, ethyl, propyl and butyl trithiometa'phosphates. The two reactants are preferably employed in substantially equimolecular proportions, although if desired an excess of the oxide or sulfide reactant may be employed to insure complete consumption of the trithiometaphosphate. The reaction takes place exothermical'ly upon mere admixture of the reactants, and when preparing any sizeable quantity of the polymer material the reaction vessel should be equipped with cooling coils or other means for dissipating the exothermic heat of reaction. The use of an inert liquid reaction medium, e. g., benzene, diethyl ether, toluene, etc., is also of assistance in absorbing theheat of reaction, and the use of such a medium constitutes" a preferred mode of operation. The reaction is usually carried out at atmospheric pressure with the reaction temperature being maintained below the atmospheric boiling point of the lowest boiling component of the reaction mixture, al-

though higher reaction temperatures and superatmospheric pressure may be employed if desired. In the interests of simplifying. the problem of heat dissipation, the reaction temperature is preferably maintained below about 200 C. Upon completion of the reaction, the

product is purified by evaporating or distilling off the reaction medium and any unreacted oxide or sulfide reactant. The reaction products themselves are very high-boiling and are distillable only under very high vacuum; accordingly, they are usually employed without further purification. In some cases they may be subjected to extraction with an organic solvent.

The following example is illustrative of the manner in which the members of the present class: of fungicidal agents may be prepared, but is not to be construed as limiting the invention:

Example 1 Approximately 42.6 parts by weight of methyl trithiometaphosphate. are dissolved in. about 36 parts by weight of diethyl ether and placed in a reaction vessel equipped with a reflux condenser and an eificient stirring device. Approximately 17.4 parts by weight of 1,2-propylene oxide are added gradually over a period of 15 minutes, during which. time the temperature increases to about 36 C. The diethyl ether is then distilled off, leaving the polymeric product as a very viscous light-tan liquid. Chemical analysis shows this material to correspond closely to the empirical formula C I-I POS and to have a molecular weight of about 1900. A similar product, taking the form of a rubber-like solid is obtained when ethylene oxide is substituted for the propylene oxide.

The fungicidal and bacterial compositions of the present invention are prepared by combining one or a mixture of the products obtained as described above with a liquid or solid inert carrier material in the conventional manner. Thus, the polymeric reaction product may be dispersed in water with the aid of adis,- persing agent to form a concentrate composition which is subsequently diluted with water to form a spray suitable for application to living plants, lumber, and other materials subject to fungus and bacteria attack. Alternatively the polymeric product may be admixed with an inert solid diluent such as talc, starch, diatomaceous earth, aluminum silicate, etc. to form a dusting composition which can be employed as such or dispersed in an aqueous or oleaginous medium to form a spray. In general, any of the conventional formulation and application techniques may be employedin employing the present fungicidal and bactericidal products, and any of the various known wetting agents, spread'ers, sticking agents, diluents, etc; may be employed in combination with any of such products. The latter are substan-tially nonphytotoxic andmaybe applied to living plants in relatively high concentrations. However, as will be apparent from the test data presented below, they are effective in very small quantities, and in the interests of economy they are usually applied at concentrations of the order of 50-2000 parts per million. Liquid concentrate compositions usually contain between about 1' and about 15 percent by weight of the active ingredient and sufiicient of anemulsifying or dispers ing agent to maintain the active ingredient uniformly dispersed in the liquid suspending medium. Solid concentrate compositions usually contain between about 5 and about 25 percent by weight of the active ingredient and, optionally, small amounts of spreading agents and other conventional adjuvants.

The following examples will illustrate the formulation of, a number of fungicidal compositions comprising members of the present class of products as the primary toxic agent, but are not to be construed as limiting the invention:

Example ll Lbs. Reaction product as prepared in Example I 2.0 Attapulgus clay 2.5 Aluminum sil 40.0

Powdered blood albumen 0.2

Example III Methyl trithiometaphosphate-ethylene oxide 2.5 Water 50.0 Sodium oleate 0.5

The reaction product and sodium oleate are added to the water, and the mixture is then passed through a colloid mill or high speed blender to obtain a concentrate composition which can be diluted 100021 with water to obtain a fungicidal spray for application to living plants.

Example V Lbs. Ethyl trithiometaphosphate-styrene oxide 10.0 Petroleum sulfonate 0.1 Kerosene extract oil 150.0

This composition is suitable for impregnating lumber.

The ingredients are mixed in a ball mill and thereafter diluted with 1200 gallons of water to obtain a spray composition containing about 1000 parts per million of the active ingredient.

Example VII Lbs.

Methyl trithiometaphosphate ethyl-ethylene oxide 4.0 Aluminum silicate 1000.0 Diatomaceous earth 500.0 Lime ars 100.0

This composition is suitable for direct application as an insecticidal and fungicidal dust.

In order to demonstrate the fungicidal activity of the present products, the following test procedure is employed: A 25-gram sample of the material to be tested and 2 drops of a non-ionic dispersing agent (Triton X-l71 manufactured by Rohm and Haas Co.) is added to enough distilled water to make 100 grams and the solution is homogenized for 3 minutes in a highspeed blender. With the blender operating, 3 grams of the liquid are removed and stirred into 75 grams of potato dextrose agar at 45 C., and the agar is transferred to a Petri dish. The agar so prepared contains 1000 p. p. m. of thematcrial to be tested. If lower concentrations are to be tested, e. g., or 100 p. p. m., l-gram portions of the concentrate composition in the blender are diluted with water accordingly. The agar is allowed to cool to room temperature, whereupon it solidifies, and a A" disc of the test fungus inoculum is placed on the surface of the agar. The inoculated agar is incubated for two days, after which the extent of fungus growth is measured and the percent inhibition of fungus growth is calculated by the formula:

Growth on test sampleX 100 Growth on blank The following tabulation presents inhibition values typical of those obtained by subjecting the present polymeric reaction products to the foregoing test procedure employing a variety of test organisms. The particular reaction product employed was the methyl trithiometaphosphate-propylene oxide polymer prepared as described in Example I, and at a concentration of 1000 p. p. m.

Test organism: Percent inhibition of growth R. solani 98.9 S. rolfsi 98.1 P. cinnamoni 100.0 P. ultimum 100.0

S. sclerotiorum 96.0 S. fructicola 97.1 B. cinerea 98.5 A. solani 100.0 Average for all organisms 98.6

The following results were obtained on several wellknown commercial fungicides:

Percent inhibition of growth at 1000 p. p. m.

Fungicide: average for eight organisms Captan" PCNB 91 Phygon 83 Fermate 96 such stated steps or composition, be employed or obtained.

We, therefore, particularly point out and distinctly claim as our invention:

1. A fungicidal composition comprising (1) the product of reaction between a lower alkali trithiometaphosphate of the formula RSPS wherein R represents an alkyl group containing from 1 to 4 carbon atoms and a compound of the general formula wherein R represents a substituent selected from the class consisting of the hydrogen atom and lower alkyl and phenyl radicals, n represents a number of the group 0- and l, and X represents a divalent element selected from the class consisting of oxygen and sulfur, and (2) a carrier therefor, said reaction product being the essential active ingredient of said composition.

2. A composition as defined by claim 1' wherein the said carrier comprises water and sufiicient of a dispersing agent to maintain the said active ingredient dispersed in said water.

3. A composition as defined by claim 2 containing between about 50 and about 2000 parts per million of the said active ingredient.

4. A fungicidal composition comprising (1) the product obtained by reacting an alkyl trithiometaphosphate of the general formula RSPS wherein R represents an alkyl group containing from 1 to 4 carbon atoms, with an alkylene oxide of the general formula wherein R represents a substituent selected from the class consisting of the hydrogen atom and lower alkyl and phenyl radicals and n represents a number of the group 0 and l, at a reaction temperature below about 200 C., and (2) a carrier therefor, said product being the essential active ingredient of said composition.

5. A composition as defined by claim 4 wherein the said alkyl trithiometaphosphate is methyl trithiometaphosphate.

6. A composition as defined by claim 4 wherein the said alkylene oxide is propylene oxide.

7. A composition as defined by claim 4 wherein the said carrier comprises water and sufficient of a dispersing agent to maintain the said active ingredient dispersed in said water.

8. A fungicidal composition comprising (1) the pr0duct obtained by reacting an alkyl trithiometaphosphate of the general formula RSPS wherein R represents an alkyl group containing from 1 to 4 carbon atoms, with an alkylene sulfide of the general formula wherein R represents a substituent selected from the class consisting of the hydrogen atom and lower alkyl and phenyl radicals and n represents a number of the group 0 and 1, at a reaction temperature below about 200 C., and (2) a carrier therefor, said product being the essential active ingredient of said composition.

9. The method of preventing and controlling the growth of fungi on plant materials which comprises applying thereto an effective amount of the composition defined by claim 1.

No references cited.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2,856,325 v October 14, 1958 Carleton B Scott et all.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, line 50, for "proplyene" read propylene column 2, 11:18 34, for "bacterial" read bactericidal column 4, line 41, for "alkali" read alkyl Signed and sealed this 3rd day of February 1959.,

(SEAL) Attest: I

KARL H, AXLINE RoBERTjc. WATSON Attesting Oflicer Commissioner of Patents 

1. A FUNGICIDAL COMPOSITION COMPRISING (1) THE PRODUCT OF REACTION BETWEEN A LOWER ALKALI TRITHIOMETAPHOSPHATE OF THE FORMULA RSPS2 WHEREIN R REPRESENTS AN ALKYL GROUP CONTAINING FROM 1 TO 4 CARBON ATOMS AND A COMPOUND OF THE GENERAL FORMULA 